Stencil



' UNITED STATES PATENT OFFICE.

WILLIAM L. DECKER, OF GREAT KILLS, NEW YORK.

STENCIL.

No Drawing.

To all whom it concern.

Be it known that WILLIAM L. DECKER, a citizen of-the United States, andresident of Great Kills, in the county of Richmond and State of NewYork, have invented certain new and useful Improvements in Stencils, ofwhich the following is a specification.

This invention relates to stencil sheets for use in the reproduction oftypewritten matter impressed therein, and my improvement refersparticularly to certain novel combinations of constituent elementsemployed by me in the treatment of paper adapted for stencil use; to thesteps of the process com prehending the treatment, and also to the newproduct which is the result of such treatment.

While the art involved in the manufacture of stencils has madeconsiderable progress, certain disadvantages are still experienced withthe products at present in the market, viz: that the treatment appliedtothe sheets takes a very long time to approach the state of drynesssuitable for stencil use; and that if left supple enough for theproduction thereon of good stenciling impressions, the surfaces of thesheets are prone through their moist and tacky condition to adhere tothe platen or types of the machine by which the impressions are createdtherein. Generally speaking, also, I have found stencil sheets which arepurchasable to be lacking in strength or tou hness, and others having atendency to bar en to a point where they do not efliciently receive typeimpressions.

Therefore, the objects of my invention are to prepare stencil sheets insuch a way that they will dry to a usable state within a few hours aftertreatment, or even in considerably less time than that; that when sodried the sheets will have and retain a high degree of strength ortoughness, the treatment adding to the original tenacity of the sheetcomprising the base of the stencil, which may be yoshino or othersuitable material; and still further, that the produced stencil willhave and vmaintain the quality of extreme suppleness, with a smooth,velvety" surface that is quite devoid of tackiness, while the structureof the stencil is impervi ous to ink and oil.-

With these and other objects in view, I

Specification of Letters Patent,

' coalesce and form insoluble lumps.

when the powder has been dissolved, I add prepare a solution of shellac,gum turpentme and soda, which is devised in the proportions ofapproximately an ounce each of the shellac, gum turpentine and soda, toa pint of water. This mixture is'boiled for about ten minutes or untilthe stated ingredients are completely dissolved. Then,

while the above solution is still boiling I add thereto a solution offish isinglass, and continue to boil the combined solution for anotherfive or ten minutes. It will be understood ,that the isinglass solutionhad been prepared in readiness for its incorporation at the proper timein the first named solution. Said isinglass solution consists offrom onehalf ounce to one ounce of fish isinglass to a quarter pint of Warmwater.

When the combined solution has been boiled for the stated period, I thenallow casein and borax should be placed at once in the water theparticles of powder ,Would But,

about six ounces of glycerin to that solution and stir the whole mixturewell together.

There have thus now been produced two separate solutions, the one, whichI will call solution No. 1, including shellac, gum tur-' pentine, sodaand fish isinglass, and the 'other, which I will call solution N0. 2,in-

and

eluding casein, borax and glycerin; the next step in the processconsists in pouring solution No. 2 into solution No. 1-while the latteris still hot, though moderated in temperature after having been boiled.These united solutions Nos. 1 and 2, which together I will call solutionNo. 3, are then stirred 'or shaken violently together until thickenedPatented Oct. 12, 1920.

Application fiIed JuIy 29, 1919. Serial No. 314,172.

or emulsified, after which solution No. 3 is oif for a time,

Before making use of solution No. 3 in the preparation of stencilsheets, I cause it to be heated up to a temperature of about 100 F thenallowing it to cool off slightly, say to about 80 F by which time a scumwill be found to have formed upon the surface of the solution. This scumis then to be removed, which is easily accomplished, because it is inthe form of a skin or gelatinous film, and can be taken ofl in a singlepiece. I

The solution No. 3 may be put into service either while still warm, orwhen cold. It is applied to the yoshino or other like paper either bydipping the sheet in the solution or by spraying the solution over thesheet, or inother known manner. I find that if the solution is appliedwhile warm itmore thoroughly penetrates the interstices of the sheetmaterial; but good results are also obtainable with the solution cold.

The saturated stencil sheets may be hung up to dry, the drying operationoccupying not over two or three hours, and sometimes a much shorterperiod, depending upon the state of the atmosphere.

In some instances the drying process may i be hastened, by passing thestencils between 20% and water 60%.

, 4, when formed, I may rubber rollers, wet wlth a drying solution,

which I will call solution No; 4, and which consists of sugar of lead,alum, glycerin and water, in the approximate proportions of sugar oflead 10%, alum 10%, glycerin Tothis solution No.

add acetic acid in the proportion of one ounce 'of aceticacid to a pintof said solution, comprehending a final drying solution which I willcall solution Excellent drying results have been obtained by me witheach of the solutions Nos. 4 and 5.

As a, modification of the above described process, wherein solution No.3 is first applied to the paper in the productionof a stencil, I maymake a combined bath of solutions Nos. 3 and 4, and treat the papertherewith in a single operation; or,instead, I may make a combined bathof'solutions Nos. 3 and 5, with which to treat the paper in a singleoperation.

When either of these combined solutions is employed the treatment shouldbe applied to the paper within a'relatively short period from the timeof their'preparation, in order that the reactions which occur eitherwhen solution No. 4 is added to solution No. 3, or when solution No. 5is added to solution No. 3 may not have had time to neutralize thesurfacing influence of either borax. and glycerin,

or a composite of alum and sugar of 'lead;

the glycerin being included to import into the product the quality ofsuppleness or softness, and the borax acts as a preservative.-

I claim 1. The new stencil which consists of loose fibered papercontaining casein as a filler, and a binding agent.

' 2. The new stencil which consists of loose paper containing casein asa filler, and a preserving agent.

3. The new stencil which consists of loose fibered paper containingcasein as a filler, and a drying agent.

4. The new stencil which consists of loose fibered paper containingcasein as a filler, a binding agent, a preserving agent, and a dryingagent.

5. The new stencil which consists of loose fibered paper containingcasein as a filler, a binding agent, a preserving agent, a softeningagent, and a drying agent.

6. The new stencil which consists of loose fibered paper containingcasein, borax, slliellac, gum-turpentine, soda, and fish ising ass. v

7. The new stencil which consists of loose fibered paper containingcasein, borax, shellac, gum-turpentine, soda, fish isinglass, sugar oflead, alum, a'nd,glycerin.

8. The method of making stencilswhich consists in treating a sheet ofloose fibered paper with a filling solution of casein, and with abinding agent, a preserving agent, a softening agent, and a dryingagent, substantially as herein set forth.

9; The method of making stencils which consists in preparing a solutionof shellac and gum turpentine, boiling said solution and adding theretoa solution of fish isinglass, allowing the combined solution-to cool OE,and, when at moderate temperature, adding thereto a solution of caseinpowder,

emulsifying the resultj ing compound solution, subsequently treating asheet of loose fibered solution, and finally 10. The method of makingstencils which consists in preparing a solution of shellac and gumturpentine, boiling said solution and adding thereto a solution,of fishisinglass, allowing the combined solution to cool paper with said dryingsaid sheet.

off, and, when at moderate temperature, ad-

ding thereto a solution of casein powder, borax and glycerin",emulsifying the resulting' compound solution, allowing said compoundsolution to stand and cool off until a skin or film is formed on itssurface, removing said skin or film, subsequently treat- Signed at GreatKills in the county of 10 Richmond and State of New York this 25th dayof July A.

D. 1919. WILLIAM L. DECKER.

